Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations declare destructiveHint and idempotentHint, but the description adds the crucial context the agent cannot get elsewhere: values are sealed immediately, are never returned by any tool or page, and only the gateway reads them. It also discloses that the write replaces the entire stored set, which matches the idempotent hint.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences with the write/replace semantics front-loaded, then the secrecy property, then the practical sourcing rule. No sentence is redundant.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Covers the destructive-write semantics, the irreversibility of reading values back, and where the values must come from — enough for a correct invocation without an output schema. It stops short of noting permission requirements or failure behavior for a non-static_headers scope.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so baseline is 3, and the description earns an extra point by clarifying that the headers object is a complete replacement set and that submitted values are write-only — meaning the agent must capture them before submitting. It doesn't add format or size constraints beyond the schema example.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource: storing a header set for an organization-held static_headers scope, replacing any stored set. The static_headers qualifier distinguishes it from set_gateway_scope_oauth_client, though that sibling is never named outright.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by the auth_mode constraint (only static_headers scopes) and the instruction to ask the person for values rather than inventing them. However, it never explicitly says when to choose this over set_gateway_scope_oauth_client or what to do if the scope has a different auth_mode.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.